Preparation of Surface-Modified Silica Particles from Rice Husk Ash and Its Composites with Degradable Polylactic Acid

A metal–matrix composite was developed by eco-friendly accumulative roll bonding process and agricultural wastes. Amorphous silica particles were obtained by heating rice husk at 600℃ and then ball milling. Amorphous silica particles as a reinforcement were embedded in a matrix of aluminum 1100. Composites with various amounts (1%, 2%, 3%, 4%, 5%, 6%, and 7%, mass fraction) of rice husk ash particles were developed. The produced aluminum–rice husk ash composites were evaluated for structural changes and mechanical properties. The scanning electron micrographs showed a uniform distribution of rice husk ash particles and were bonded well with the aluminum matrix after 10 cycles. By increasing the rice husk ash content, the composite strength increases first and then becomes constant because of the inappropriate connection of aluminum sheets. Increasing the rice husk ash content of the composite causes the change from the ductile to a relatively brittle type of fracture.

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Nanoengineering of Surface Modified Silica Particles to Form Core-Shell and HollowNanospheres of Iron Oxide

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2007.854 ◽

2007 ◽

Vol 7 (10) ◽

pp. 3662-3669 ◽

Cited By ~ 4

Author(s):

Neha Hebalkar ◽

P. Radhika ◽

B. Sreedhar ◽

M. Lakshmi Kantam

Keyword(s):

Iron Oxide ◽

Silica Particles ◽

Core Shell ◽

Modified Silica ◽

Surface Modified

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Enzymatic synthesis and characterization of polycaprolactone by using immobilized lipase onto a surface-modified renewable carrier

Polish Journal of Chemical Technology ◽

10.1515/pjct-2016-0060 ◽

2016 ◽

Vol 18 (3) ◽

pp. 134-140 ◽

Cited By ~ 11

Author(s):

Cansu Ulker ◽

Nurefsan Gokalp ◽

Yuksel Guvenilir

Keyword(s):

Rice Husk ◽

Rice Husk Ash ◽

Immobilized Lipase ◽

Covalent Binding ◽

Aqueous Media ◽

Energy Saving Process ◽

Surface Modified ◽

First Time ◽

Polymerization Conditions

Abstract In the present study, rice husk ash, which is a renewable and abundant material, was utilized as a carrier for lipase immobilization for the first time. Poly (ε-caprolactone) synthesis was successfully achieved by the new enzymatic catalyst: Candida antarctica lipase B immobilized onto surface-modified rice husk ashes by covalent binding. It was aimed to obtain optimum polymerization conditions at which highest molecular weight was reached and characterize the polymer produced. Moreover, thermal stability and effectiveness of the new biocatalyst in non-aqueous media were also shown with successful polymerization reactions. In addition, by using the new enzyme preparation, ε-caprolactone was able to be polymerized even at 30°C, which was promising for an energy saving process. Consequently, this work provides a new alternative route for poly (ε-caprolactone) synthesis.

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SYNTHESIS OF PURE SILICA FROM RICE HUSK ASH AS AN ANTI–CAKING AGENT FOR FERTILIZER INDUSTRY IN VIETNAM

Vietnam Journal of Science and Technology ◽

10.15625/2525-2518/55/1b/12108 ◽

2018 ◽

Vol 55 (1B) ◽

pp. 193

Author(s):

Nguyen Huu Hieu

Keyword(s):

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Rice Husk ◽

Rice Husk Ash ◽

Silica Particles ◽

Average Particle ◽

X Ray ◽

Pure Silica ◽

Npk Fertilizer

Pure silica particles have been successfully synthesized from rice husk ash (RHA) by precipitation method. The characterization of silica was performed by X–ray diffraction, X–ray fluorescence, Fourier transform infrared spectroscopy, Brunauer–Emmett–Teller specific surface area, and transmission electron microscopy. The characterization results show that the obtained amorphous silica was 99.8 % purity with average particle size of 5–10 nm, and high specific surface area of 224 m2/g. Additionally, for the first time that RHA–silica was successfully applied as an anti–caking agent for a NPK–fertilizer. A suitable content of silica was evaluated through the level of anti–caking. The testing results show that with only 1.5 wt% of RHA–silica particles could replace kaolin as an anti–caking agent for the NPK–fertilizer.

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Fabrication and Evaluation of the Novel Elastomer Based Nanocomposite with Pressure Sensing Function

Materials Science Forum ◽

10.4028/www.scientific.net/msf.544-545.741 ◽

2007 ◽

Vol 544-545 ◽

pp. 741-744

Author(s):

Youn Gyu Han ◽

Tomonori Shibata ◽

Rajagopalan Ramaseshan ◽

Tohru Sekino ◽

Koichi Niihara

Keyword(s):

High Performance ◽

Low Cost ◽

Carbon Particle ◽

Conductive Filler ◽

Silica Particles ◽

Modified Silica ◽

Pressure Sensing ◽

Carbon Particles ◽

Pressure Sensitive ◽

Surface Modified

A novel organic/inorganic composite material which can work as a pressure sensor has been synthesized. This composite basically contains nano-sized carbon particles as conductive filler into an elastomer matrix to achieve pressure sensitive function. The superior pressure sensitive effect was showed at 0.88vol% of carbon particles while in the previous study the micro-sized carbon particle was required above 30vol%. In addition, nano-sized silica particles were added to reinforce electrical insulation properties and to improve the pressure sensing reliability of the composite. The addition of the surface modified silica improved better both the sensing performance and the mechanical strength than the composite containing non-modified silica particles. These polymer-based sensors have economical advantage due to low cost production regardless of the high performance.

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